i'd use diesel.. Wallas is awesome!
I bought my boat with propane installed - it was all about 30 years old so when I replaced it I decided to look for the best I could afford... my 31' trimaran 'Ceil' has a yanmar diesel so I decided this was a better option than keeping the propane.
I decided on a Wallas diesel stove/heater unit. This unit is the size of a laptop (it mounts in a counter top - so it won't work on a bulkhead... but they do make a heater/only that does... and works so well it's kinda hard to believe. It came with a 2 gal daytank (actually it's closer to a 5 day tank) but I can plumb it into my main tank if needed.
Why this unit?
1. There is NO DIESEL SMELL!! period.
2. it's diesel but exhausts outside using a flexible insulated tube (needs to be permanent through hull -it's not a temp exhaust hose.. - so it was easy to thread it to where it needed to go. The exhaust hose only warms up the cabinet it goes through - no fire danger. I have a trimaran so I exhausted just under the port wing.
3. It is electronically controlled (I even installed a cabin thermostat and timer with mine which i designed - but they now sell one)
4. The wallas is a stove top (glass panel which is large enough when opened for a two qt pot and a frying pan).
5. When the stove is lit (automatic) and the top closed the unit has a fan that comes on and changes it into a space heater. The closed lid also completely insulates the cooking surface so you can put anything on the lid and it will not even get warm. When cooking the lid is open and functions as a back sptwolash for the stove. The stove and heater are lit and controlled with a switch and knob. No lighting anything - ever. No open flames at all.
6. because it's exhausted outside the unit DRYS OUT THE CABIN AIR!! This really is important if you sail in humid climes or when it's so cold that even your breath wets surfaces in the cabin leading to mildew.
7. It is not quite silent because it has a fan for the space heating part but it's pretty quiet.
8. When used as a cooktop it has 'pot holders' that keep things from sliding off the tempered glass cooktop.
9. it heats up a pot to boiling in about 5 minutes.
As for the comment that using propane for cooking/heating saves fuel for the engine... diesel has far more energy per lb than propane (or gas for that matter) and far less fire issues.. You have to carry propane tanks along with the propane gas (i tried carrying the propane in a baggy but it didn't work too well ;-0 ) so you are putting more lbs and square footage (taking up space) in the boat (i have a trimaran so weight is important) and more complexity. I'd rather put an aux diesel tank in and then I'd actually have MORE fuel for the engine in a bind (i'd just have to run the stove/heater less).
FYI the service dept for the wallas is great too. They answered questions and shipped parts when asked very quickly. That makes my $0.25 worth... good luck with your choice!
Last edited by catandahalf; 12-06-2011 at 10:41 AM.